Question
Last October 1st, a patient with facial paralysis underwent acupuncture treatment for over a month and their facial expressions returned to normal. The doctor assessed the recovery as good. However, by January 2015, the patient noticed frequent twitching of the nerve in the eyelid on the affected side, which could occasionally be noticed by others. Currently, there is a noticeable swelling in the eyelid on the affected side. A electromyogram (EMG) test was completed on January 29th, with the results showing that no abnormalities were found in the tested muscles. The amplitude of the facial nerve on the left side was relatively lower than that on the right side, specifically with the orbicularis oris muscle differing by 0.5ms, the orbicularis oculi muscle differing by 1.3ms, and the buccinator muscle differing by 2.1ms.
Answer
Eyelid twitching is common in several situations: first, when there is no abnormality in the muscle itself, but it is merely due to overuse of the eyes. Second, when the orbicularis oculi muscle affected by facial paralysis has not fully recovered and is relatively weak. Third, when facial paralysis may have stimulated the muscle excessively, leading to increased muscle excitability. Due to a lack of physical examination information, it is not possible to determine the exact cause.